I found the Python more readable even though I have written programs in Clojure and never written programs in Python. In fact I'd be willing to bet that Python-like syntax would be found to be more readable than Lisp-like syntax for programmers with N years of experience in that language, if such a study could be conducted. (ie, I'd bet that an average programmer with 5 years of Python experience and nothing else can correctly read programs faster than an average programmer with 5 years of Clojure experience and nothing else (not that the latter exists)).
True, but for instance I know neither Python nor Clojure, and yet Python looks more accessible on first glance - even though I have some experience with other LISPs.
I've started using Clojure after many years of Ruby and I have to say the parentheses are a non-issue. Emacs and many IDEs automatically balance the parens for you (see e.g. paredit). Once your eyes learn to ignore the bracket soup, the code starts looking an awful lot like Python (cmp. Emacs Lisp indention with Python semantic indention).